Sofa convertible into bunk bed

ABSTRACT

A sofa bed is convertible to a bunk bed using front and rear links coacting with front and rear cylinders to lift a bunk frame from the sofa position, in which it is used for seating, to a bunk bed position where seat cushions are used on the bunk and a mattress is available for a lower bunk, the cylinders being lockable and a brace and latter are deployable and lockable to secure the bunk.

CLAIM OF PRIORITY

This application claims priority on Provisional application Ser. No. 62/259,956 filed Nov. 26, 2015, having the same title and inventor as the present application and having attorney docket No. CU-72546.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates generally to a furniture assembly, and more particularly, to a sofa bed convertible into a bunk bed having a mechanism being compact and particularly adaptable to placement in vehicles or dimensionally limited locations.

BACKGROUND

A sofa usually has a seating surface, a back surface, and arms, while a bunk bed has a plurality of sleeping surfaces oriented with at least a portion of a top sleeping surface vertically displaced above a lower sleeping surface. The convertible bunk bed stores the bed in the area above the seating surface. In the prior art EP2110054 (A1) “Mechanism for bunk beds and sofa-bed comprising this mechanism” appears to use curved links to enable a bunk bed to be moved vertically to a position above the lower bed. In the prior art CN202553068 (U) “Novel dual-use sofa” the arms of the sofa are pivoted so that the top bunk is inverted when the sofa is in the seating position and when rotated 180 degrees upwardly so that the frame inverts to present the opposite surface for sleeping.

The former utilizes a mechanism of some complexity for ease of deployment, but lacks a desirable level of rigidity and support when in the bunk bed position. The latter requires a substantial range of motion for movement of significant mass in directions atypical to the user.

In the prior art U.S. Pat. No. 405,495 “Foldable Bunk Bed Assembly” a hinged outer portion of a seat back converts to upper bunk but requires mounting on a wall or bulkhead. U.S. Pat. No. 7,360,261 “Sofa” hinges the seat back to the seat back frame pivoting upward to a bunk bed position. U.S. Pat. No. 4,592,101, “Sofa-bunk bed combination with pivotable cushion” pivots and elevates the seat back to be used as the top bunk. Published application CN202553068U “Novel dual-use sofa” has a hinged front and rear portion with overlapping platforms in which the front portion rotates forwardly and upwardly and inverts, the upper inverted platform forming the bunk bed and the lower platform forming the lower bed. Published application EP2110054 (A1) “Mechanism for bunk beds and sofa-bed comprising this mechanism” uses complex linkage to raise and invert a lower seat platform so that when inverted and fully raised it forms a top bed in a bunk bed.

The present invention solves problems in the prior art described above. The sofa convertible to a bunk bed described herein provides a superior sleeping surfaces in a more compact footprint and range of motion, while additionally providing structure for mounting in vehicles and clearance for mounting such securement apparatus as seat belts and harness over that of the prior art sofa bunk beds. Links acting in combination with pneumatic cylinders or other telescoping struts provide mechanical advantage and locking for a trussile support mechanism. The frame design additionally incorporates guards and ladders in a unitary assemblage.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a front elevational view of an embodiment of the sofa convertible to a bunk bed in the bunk bed position.

FIG. 2 is a side elevational view of an embodiment of the sofa convertible to a bunk bed in the bunk bed position.

FIG. 3 a perspective view of an embodiment of the sofa convertible to a bunk bed in the bunk bed position.

FIG. 4 is a front elevational view of an embodiment of the sofa convertible to a bunk bed in the sofa position.

FIG. 5 is a side elevational view of an embodiment of the sofa convertible to a bunk bed in the sofa position.

FIG. 6 is a top plan view of an embodiment of the sofa convertible to a bunk bed with the front guard undeployed.

FIG. 7 is a perspective view of an embodiment of the sofa convertible to a bunk bed in the sofa position.

FIG. 8 is a perspective view of an embodiment of the sofa convertible to a bunk bed in the mid-position.

FIG. 9 is a sectional elevational view of an embodiment of the sofa convertible to a bunk bed in the sofa position.

FIG. 10 is a sectional elevational view of an embodiment of the sofa convertible to a bunk bed in the mid-position.

FIG. 11 is a sectional elevational view of an embodiment of the sofa convertible to a bunk bed in the bunk bed position taken on line A-A of FIG. 1.

FIG. 12 is a perspective view of an embodiment of the sofa with mattress and cushions shown.

FIG. 13 is a perspective view of an embodiment of the sofa with mattress and cushions shown with the bunk configured for sleeping.

FIG. 14 is a perspective view of an embodiment of the sofa back cushion. FIG. 1 is a front elevational view of an embodiment of the sofa convertible to a bunk bed in the bunk bed position.

FIG. 15 is a side elevational view of an embodiment of the sofa having a first alternative track and gas cylinder pivot location.

FIG. 16 is a side elevational view of an embodiment of the sofa having a second alternative track and gas cylinder pivot location.

FIG. 17 is a side elevational view of an embodiment of the sofa having a third alternative track and gas cylinder pivot location.

FIG. 18 is a side elevational view of an embodiment of the sofa having a fourth alternative track and gas cylinder pivot location.

Terms such as front, side, rear, left and right as may be used herein are relative terms referring to the sofa convertible to a bunk bed and are not limited to its mounting, installation or arrangement to any particular position or space in a room or vehicle or to which direction a person is oriented on the sofa or bed. Unless otherwise qualified left and right refer to the point of view of a person sitting on the sofa.

DETAILED DESCRIPTION

Referring to the drawings, the sofa bed 10 of this invention is generally shown. The sofa bed 10 includes base frame assembly 12 with side frames 14 and 16 interconnected by rear transverse frame 18 and front transverse frame 20. Side frames 14 and 16 may be formed of perimetrical frame members, solid plates 22, 24, or a combination. Each plate 22, 24 is formed and arranged so as to have an angled, straight tracks or guide slots 26, 28.

Advantages to using solid sheet or plate could include the substantial elimination of components requiring assembly; the ability to be formed through automated manufacturing means such as laser cutting or other appropriate machining, and the elimination of braces between the tracks or guide slots 26, 28 which can be more easily maintained in position by the presence of the solid web between them.

The upper bunk frame 30 is formed with a lower perimetrical frame 32 and a rear guardrail assembly 34. On each side is a side guard 36, 38.

Upper bunk frame 30, when deployed in the bunk bed position is primarily supported by right and left front links 40, 42 and right and left rear links 44, 46. The right and left front links 40, 42 are dynamically actuated and statically fixed (when locked) by right and left front cylinders, 48, 50. The right and left rear links 44, 46 are dynamically actuated and statically fixed (when locked) by right and left rear cylinders, 52, 54. Cylinders 48, 50, 52, 54 are preferably pneumatic cylinders but equivalents such as hydraulic cylinders, or spring, screw or rack and pinion mechanisms could be used to perform the function of assisting in raising bunk bed frame 30 and maintaining it in the bunk bed position 56.

In the bunk bed position 56 ladder 58 is rotated to a vertical position and locked, front brace 60 is rotated to a vertical position and locked with locking mechanism 64. Front guard 62 is rotated to a vertical position and locked with locking mechanism 64. Extending upwardly from side frames 14 and 16 are tabs 66, 68. These may be formed with frame members or plate or a combination.

In an embodiment, here described with reference to left links 42, 46 and cylinders 50, 54, which are shown in the sectional views of FIG. 10, 11 and 12, left front link 42 has a top pivot 70 and bottom pivot 72. Left rear link 46 has a top pivot 74 and a bottom pivot 76. Left front cylinder 50 has an upper pivot connects at link bottom pivot 72 and a lower cylinder pivot 82. Left rear cylinder 54 has an upper pivot 84 and a lower pivot 84. The relative terms top, bottom, upper and lower refer to the orientation of the components when in the bunk bed position.

Front link bottom pivot 72 is formed and arranged to slide in guide slot 28 thereby providing the range of motion needed to permit the bunk frame 30 to move vertically, while also remaining in a substantially horizontal orientation. Rear link bottom pivot 76 is mounted to tab 68 in a fixed location so as to permit link 46 to rotate about pivot 76 front link top pivot 70 and rear link top pivot 74 are mounted in fixed front and rear locations on upper bunk frame 30.

Left front cylinder 50 is mounted with front cylinder lower pivot 82 in a fixed location on plate 22 and front cylinder upper pivot connected at front link bottom pivot 72. As pivot 72 slides in angled slot 28 pivot 84 causes compression of cylinder 50, however as bunk frame 30 is moved first upwardly and frontwardly and then continuing upwardly and rearwardly, cylinder 50 extends to aid in raising frame 30 to the bunk bed position 56. This movement works together with rear cylinder 54 and rear link 46 through mounting rear cylinder lower pivot 84 on tab 68 with rear cylinder upper pivot 84 mounted to the median portion of rear link 46. These references refer to the sectional views and the opposite side will be a mirror image of that shown and described.

As frame 30 is moved from the sofa position toward the mid position, left rear cylinder 54 compresses slightly, but as link 46 passes the axis of cylinder 54, then cylinder 54 urges link 46 upward toward bunk bed position 56. In bunk bed position 56 each of right and left front cylinders, 48, 50 and right and left rear cylinders, 52, 54 may be locked. At this time the ladder 58 and brace 60 are also locked at lock mechanisms 64. The bed is converted to a sofa in substantially the reverse manner.

The geometry of links right and left front links 40, 42, right and left rear links 44, 46 and their respective front link top pivot 70 front link bottom pivot 72, rear link top pivot 74, rear link bottom pivot 76, front cylinder upper pivot 80, front cylinder lower pivot 82, rear cylinder upper pivot 84 and rear cylinder lower pivot 86 is such that manual deployment may be accomplished as described, while alternative cylinders and other actuators and controls could be utilized for automatic deployment.

The mattress 90 shown in FIGS. 3, 11, 12 and 13 and the cushions shown in FIGS. 12 and 13 can advantageously be arranged so that the mattress 90 remains in the same position, either under the frame 30 when in the sofa position or available for sleeping in the bunk bed position 56. Seat cushion 92 may be thick enough to serve as a top mattress on the top bunk, or seat back cushion 94 could be formed in a foldable manner and unfolded from the sofa seat back configuration to a sleeping configuration. Cushion 92 could remain and be combined with cushion 94 for double the thickness.

In the alternative embodiments shown in FIGS. 15, 16, 17 and 18 sectional views at section A-A of FIG. 1, different configurations of tracks and links provide properties that may be tailored to specifically desired performance relative to the movement, compactness, strength and mechanical rigidity, noting sofa bed 10 right side frame 14 solid plates 22 guide slot 28 right front link 40 right rear link 44, right front cylinders 48 and right rear cylinder, 54 generally formed and arranged as described above but with specific variations controlling the movement of the bunk bed assembly as it is raised and lowered. In FIG. 15 and FIG. 16 slot 28 has a lower straight portion, a forwardly curving intermediate portion and an upwardly curving upward portion. FIG. 16 has increased size component sections and reinforcing members on plate 22. FIGS. 17 and 18 have some of the components removed for clarity, but show slot 28 in different configurations. FIG. 17 shows slot 28 in a nearly vertical orientation, with a generally straight lower portion an intermediate curve and a generally straight upward portion. In FIG. 18 slot 28 has a near vertical lower portion a forwardly curving intermediate portion and a straight upper portion. 

1. A sofa convertible into bunk bed comprising: a base frame assembly having a side frame; an upper bunk frame; a front link and a rear link rotatably connecting the base frame to the upper bunk frame such that the upper bunk frame rotates between a bunk bed position and a sofa position, wherein the front link and the rear link rotatably connect the base frame to the upper bunk frame such that the upper bunk frame moves vertically while also remaining in a substantially horizontal orientation when the upper bunk frame rotates between the bunk bed position and the sofa position.
 2. The sofa convertible into bunk bed of claim 1, wherein the front link includes a top pivot connected to the upper bunk frame and a bottom pivot connected to the side frame; and the rear link includes a top pivot connected to the upper bunk frame and a bottom pivot connected to the side frame.
 3. The sofa convertible into bunk bed of claim 1, wherein the side frame includes a guide slot; the front link includes a top pivot pivotally connected to the upper bunk frame and a bottom pivot formed and arranged to slide in the guide slot; the guide slot is sized and shaped to provide the range of motion needed to permit the bunk frame to move vertically, while also remaining in a substantially horizontal orientation; the rear link includes a top pivot pivotally connected to the upper bunk frame and a bottom pivot pivotally connected to the side frame.
 4. The sofa convertible into bunk bed of claim 3, further comprising: a front cylinder including an upper pivot pivotally connected to the front link bottom pivot and a lower pivot pivotally connected to a fixed location on the side frame.
 5. The sofa convertible into bunk bed of claim 2, further comprising: a rear cylinder including an upper pivot pivotally connected to a median portion of the rear link and a lower pivot pivotally connected to a fixed location on the side frame.
 6. The sofa convertible into bunk bed of claim 1, further comprising: a ladder rotatably connected to the base frame and configured to be rotated to a vertical position and locked; a front brace rotatably connected to the ladder and configured to be rotated to a vertical position and locked with a locking mechanism.
 7. The sofa convertible into bunk bed of claim 6, wherein: the ladder rests over an upper portion of the base frame when in the sofa position, and rotates in a first direction to the vertical position; and the front brace rotates towards a second direction opposite the first direction.
 8. The sofa convertible into bunk bed of claim 3, wherein the side frame is a plate formed and arranged so as to have the guide slot, wherein the guide slot includes one or more of an angled track portion, a straight track portion and a curved track portion.
 9. The sofa convertible into bunk bed of claim 3, wherein the guide slot includes a lower straight track portion, a forwardly curving intermediate track portion and an upwardly curving upward track portion.
 10. The sofa convertible into bunk bed of claim 3, wherein the guide slot includes a generally straight lower track portion, and intermediate curve track portion and a generally straight upward track portion.
 11. The sofa convertible into bunk bed of claim 3, wherein the guide slot includes a near vertical lower track portion, a forwardly curving intermediate track portion, and a straight upper track portion.
 12. The sofa convertible into bunk bed of claim 1, further comprising a mattress positioned on the base frame; and one or more cushions positioned on the upper bunk frame, wherein the mattress and the cushions are arranged such that the mattress remains in the same position when the upper bunk frame is in the bunk bed position and the sofa position.
 13. The sofa convertible into bunk bed of claim 1, wherein the base frame comprises: a lower perimetrical frame; a rear guardrail assembly; and a side guard.
 14. A sofa convertible into bunk bed comprising: a base frame assembly having a side frame, the side frame having a guide slot, and the guide slot including one or more of an angled track portion, a straight track portion and a curved track portion; an upper bunk frame; a front link and a rear link rotatably connecting the base frame to the upper bunk frame such that the upper bunk frame rotates between a bunk bed position and a sofa position, wherein the front link includes a top pivot pivotally connected to the upper bunk frame and a bottom pivot formed and arranged to slide in the guide slot, and the rear link includes a top pivot pivotally connected to the upper bunk frame and a bottom pivot pivotally connected to the side frame.
 15. The sofa convertible into bunk bed of claim 14, further comprising: a front cylinder including an upper pivot pivotally connected to the front link bottom pivot and a lower pivot pivotally connected to a fixed location on the side frame.
 16. The sofa convertible into bunk bed of claim 14, further comprising: a rear cylinder including an upper pivot pivotally connected to a median portion of the rear link and a lower pivot pivotally connected to a fixed location on the side frame.
 17. The sofa convertible into bunk bed of claim 14, further comprising: a ladder rotatably connected to the base frame and configured to be rotated to a vertical position and locked; a front brace rotatably connected to the ladder and configured to be rotated to a vertical position and locked with a locking mechanism.
 18. The sofa convertible into bunk bed of claim 14, wherein the guide slot includes a lower straight track portion, a forwardly curving intermediate track portion and an upwardly curving upward track portion.
 19. The sofa convertible into bunk bed of claim 14, wherein the guide slot includes a generally straight lower track portion, and intermediate curve track portion and a generally straight upward track portion.
 20. The sofa convertible into bunk bed of claim 14, wherein the guide slot includes a near vertical lower track portion, a forwardly curving intermediate track portion, and a straight upper track portion. 